[feat] Allow users define custom log handlers and attach them to the framework

[dmargala]

This PR adds support for defining a custom log handler that can be specified in the reframe configuration file.

For example, adding a plugin log handler would look something like the following:

class PlugInLogHandler(logging.Handler):
    def emit(self, record):
        custom_logger.log(record)

def _create_plugin_handler(site_config, handlers_group):
    return PlugInLogHandler()

from reframe.core.logging import register_plugin_handler
register_plugin_handler(_create_plugin_handler)

There is some prior art in the reframe code base for a similar capability for custom launchers (see extending-the-framework section of the docs). There may be some other ways to implement this by extending the existing Stream or File log handlers to accept custom stream or file objects.

closes #3270

[pep8speaks]

Hello @dmargala, Thank you for updating!

Cheers! There are no PEP8 issues in this Pull Request!Do see the ReFrame Coding Style Guide

Comment last updated at 2024-10-18 08:09:27 UTC

[vkarak]

Thanks for the PR! I have some suggestions on how to make this idea more in sync with the similar idea of custom launchers and schedulers.

We should also add a small documentation section about it in the "how to".

[vkarak]

Lgtm, just some style nitpicking.

[dmargala]

Thanks. I applied suggestions and also fixed indent spacing in the examples (the spacing in the code blocks had inherited the 3-space indents, I changed it to 4-spaces.

[vkarak]

Thanks!